Prediction of stratiform clouds: Results fiom a 5-day forecast with a global model

A parameterization scheme of stratiform condensation including cloud water content as a prognostic variable (Sundqvist, Q. J. Roy. Met. Soc., 1978) is implemented in a global numerical prediction model. A phenomenological investigation of the model cloud behaviour during a 5-day integration is carried out. In the analysis the resulting clouds have been grouped into three classes, low, middle and high, so that a colour picture presentation is possible. Those pictures are also compared with satellite pictures. Furthermore, some details of the model cloud water content and cover are shown with the aid of cross-sections. The results exhibit a good deal of realism and it is suggested that further experiments be performed in which dynamical effects for the model clouds are analyzed.